This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. The goal of this collaboration with Guy Perkins of NCMIR is to investigate the mechanism by which the protein sestrin regulates target of rapamycin (TOR). The electron microscopy and mitochondrial microanatomy resources of the NCMIR will be used to elucidate structural phenotypes of sestrin knock-out skeletal and heart muscle in Drosophila fly and therapeutic intervention.